SQLSERVER 2005 递归查询 .

项目中有用户组表UserGroup如下：

其中PID表示当前组的上级组

表数据如下：

现在想查询出顶级组[没有上级组叫顶级组]A1组的所有子孙组ID,SQL如下：

--查询父节点with RTU1 as(select id ,pid from UserGroup),RTU2 as(select * from RTU1 where id=26union allselect RTU1.* from RTU2 inner join RTU1 --on myT2.id=myT.PIDon RTU2.PID=RTU1.ID)select * from RTU2

查询结果如下：

id????????? pid
----------- -----------
26????????? 23
23????????? 20
20????????? 6
6?????????? NULL

(4 行受影响)

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--查询某一父节点的所有子节点
with
?RTD1 as(
??select id,name,fid from ProductType
?),
?RTD2 as(
??select id,name,fid from RTD1 where id=10103
??union all
??select RTD1.* from RTD2 inner join RTD1
??on RTD2.id=RTD1.FID
?)
select * from RTD2

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--查询某一父节点的所有子节点
with c as (
???? select * from producTtype where Id =10103
? union all
??? select a.* from producTtype as a
??????? join c on a.fid = c.Id)
?select * FROM? c

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